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31.
Alessandro Marchetti Chiara Piccini Sergio Santucci Igino Chiuchiarelli Rosa Francaviglia 《CATENA》2011,85(3):267-273
Soil surveys are an essential source of information for land management although a limited budget often reduces the amount of data available. Even if the dataset is limited, geostatistics can provide a valid estimation tool through a weighted moving average interpolation (kriging). Often, however, the spatial variability of soil properties appears smoothed and short range variability is underestimated by this kind of interpolation technique. A more realistic distribution of a given variable on the territory can be obtained through models based on stochastic simulation. 相似文献
32.
Sharon L Deem Andrew J Noss Rosa Leny Cuéllar William B Karesh 《Journal of zoo and wildlife medicine》2005,36(4):598-605
Bolivia has a total of 47 species of Psittacidae, seven of which have been identified in our study site, the semiarid Gran Chaco of the Isoso. One species, the blue-fronted parrot (Amazona aestiva), is frequently captured by local Isose?o Guaraní Indians for exploitation on the national and international market. These birds are often temporarily housed in small villages under unhygienic conditions with poultry and other domestic species. On occasion, these parrots escape back to the wild. Additionally, many of these birds are kept as pets or are used to lure wild. parrots within slingshot range for subsequent capture. In this study, we evaluated the health status, including the level of exposure to selected infectious agents, in the wild-caught captive birds and free-ranging birds. Physical examinations were performed, and blood was collected, from 54 live birds (20 captive and 34 free-ranging). Feces were collected from 15 birds (seven captive and eight free-ranging). Necropsies were also performed on four recently dead wild-caught birds. On serologic testing, no birds were found to have antibodies to avian influenza virus, Chlamydophila psittaci, infectious bronchitis virus, infectious bursal disease virus, infectious laryngotracheitis virus, Marek's disease virus, paramyxovirus-1, paramyxovirus-2, paramyxovirus-3, polyomavirus, eastern equine encephalitis virus, western equine encephalitis virus, or Venezuelan equine encephalitis virus. Positive antibody titers were found for psittacine herpesvirus (8/44, 18.2%), Aspergillus spp. (3/51, 5.9%), and Salmonella pullorum (33/49, 67.3%). All three of the birds that tested antibody positive for Aspergillus spp. were captive, whereas six of the eight and 15 of the 33 birds that tested positive for psittacine herpesvirus and S. pullorum, respectively, were wild. 相似文献
33.
Clinical chemical determinations were carried out on blood removed by cardiac puncture from 49 mink affected with Aleutian disease and 25 normal animals and the respective differences tested for statistical significance. Blood urea nitrogen, serum total protein and globulin, thymol turbidity, glutamic oxalacetic and glutamic pyruvic transaminases and amylase were definitely elevated in the affected animals whereas serum calcium, albumin and A/G ratio were depressed. No statistically significant difference was apparent between the two groups in the comparison of inorganic phosphorus, alkaline and acid phosphatases, bilirubin, total cholesterol and esters, cephalin-cholesterol flocculation (3+ in each case), sodium, potassium, chloride, CO2-combining power, leucine aminopeptidase and lactic dehydrogenase (means: over 2,000 u./ml.). For both the control and affected mink, the distribution of serum lactic dehydrogenase isozymes resembled that of human homologous serum hepatitis. Electrophoresis of serum proteins confirmed earlier findings of hypergammaglobulinemia in the diseased animals but a fast-moving or pre-albumin component, averaging 4% of the total protein, occurred in both the diseased and normal mink. 相似文献
34.
I. B. Griffiths M. I. Gallego Ligia S. De Leon 《Tropical animal health and production》1984,16(4):219-223
Of 4,144 serum samples collected from cows on 113 farms from eight areas of Colombia 3.3% had positive and 8.8% inconclusive titres to Brucella abortus, 21.7, 6.3, 1.6, 0.6 and 0.7% of cows had positive titres to Leptospira serovars hardjo, pomona, canicola, icterohaemorrhagiae and grippotyphosa respectively. Questionnaires completed on 110 farms revealed that 6, 2.5 and 4.6% of cows had had metritis, aborted or retained their placentas respectively in the previous 12 months. Trichomonas foetus and Campylobacter fetus were isolated from 13.7% and 15% of the bulls sampled on 103 farms. Six and two bulls had inconclusive and positive titres to Brucella abortus. Eight and 23 bulls had positive titres to pomona and hardjo. The results were discussed and remedies for control suggested. 相似文献
35.
Virucidal efficacy of four new disinfectants 总被引:5,自引:0,他引:5
Eleraky NZ Potgieter LN Kennedy MA 《Journal of the American Animal Hospital Association》2002,38(3):231-234
Virucidal efficacy was evaluated for four recently available disinfectants: chlorine dioxide, potassium peroxymonosulfate, a quaternary ammonium compound, and citricidal (grapefruit extract). Sodium hypochlorite (3%) and tap water were used as positive and negative controls respectively. Feline herpesvirus, feline calicivirus, and feline parvovirus were exposed to the manufacturers' recommended dilutions of the evaluated disinfectants. Both chlorine dioxide and potassium peroxymonosulfate completely inactivated the three viruses used in this study. These disinfectants can aid in controlling nosocomial transmission of viruses with less of the deleterious effects of sodium hypochlorite. The quaternary ammonium compound evaluated in this study and citricidal were not effective against feline calicivirus and feline parvovirus. 相似文献
36.
G. La Rosa M. Muscillo A. Di Grazia S. Fontana M. Iaconelli M. Tollis 《Zoonoses and public health》2006,53(6):257-265
Porcine enteroviruses (PEVs) and teschoviruses (PTVs) are described as causative agents of neurological disorders, fertility disorders and dermal lesions of swine. Difficulties in the serological detection of these viruses may lead to a significant underestimation of infections with clinical symptoms. With the recent availability of genome sequence data for all the serotypes, molecular diagnosis is a possibility. The present study describes a new approach to molecular ‘serotyping’ of PTVs and PEV‐B viruses, involving the amplification and sequencing of a genomic fragment of the VP1 coding region. A molecular characterization of Italian entero‐teschovirus isolates was performed using a set of previously published and newly designed polymerase chain reaction primers. A total of 33 porcine isolates and 10 reference strains were analysed. Porcine enterovirus‐B samples were first diagnosed as positive for enterovirus by amplification of the 5′‐non‐translated region. Samples were then typed by amplification and sequencing of a portion of the VP1 coding region. Porcine enterovirus‐A and PTVs were detected by a published assay in the 5′‐NC region that allows them to be differentiated according to the size of amplification product, using the same set of primers. For serotype characterization of PTV, we evaluated four different regions: the N terminus of the capsid protein VP2, the region encoding for RNA‐dependent RNA polymerase, and the capsid VP1 and VP4 regions. The newly designed primers in the VP1 region was proved to be broad in range and suitable for serotype assessment and therefore constitute a useful diagnostic tool for molecular diagnosis of porcine teschovirus/enterovirus strains and for the study of molecular epidemiology and evolution of these viruses. 相似文献
37.
Agostino Sorgonà Maria Rosa AbenavoliPietro Giorgio Gringeri Giovanni Cacco 《Scientia Horticulturae》2006
Nitrogen use efficiency (NUE) definitions, commonly used in literature, are evaluated in response to nitrate availability in four citrus rootstocks, Rough Lemon (Citrus jambhiri Lush) (RL), Sweet Orange (Citrus sinensis (L.) Osbeck) (SwO), Cleopatra Mandarin (Citrus reshni Hort ex Tan.) (CM) and Sour Orange (Citrus aurantium L.) (SO). The application of diverse definitions determine different characterizations in N-efficiency among rootstocks. Nitrogen utilization efficiency (NUtE) and nitrogen efficiency ratio (NER) determine equal level of nitrogen efficiency among all rootstocks. Total nitrogen accumulation (TNA), nitrogen uptake efficiency (NUpE), shoot dry weight (SDW) and total leaf area (TLA) response curves produce the same NUE characterization: SO and SwO were nitrate use efficient and inefficient rootstocks, respectively, while the RL and CM exhibit superior and inferior genetic potential, respectively. 相似文献
38.
Pietro Rocculi Emiliano Cocci Santina Romani Giampiero Sacchetti Marco Dalla Rosa 《Postharvest Biology and Technology》2009,51(3):371-377
The effects of both 1-MCP treatment of pineapples and packaging of their fresh-cut products with an alternative modified atmosphere (MA: 86.13 kPa N2O, 10.13 kPa O2 and 5.07 kPa CO2) on physiological and quality changes of these minimally processed products were investigated. Fresh-cut fruit treated or not with 1-MCP were packed in Air or in MA and were stored at 4 °C for 10 d. The following parameters were monitored during storage: ripening index; O2, CO2 and C2H4 in the package headspace; firmness and colour. Microbial spoilage of MP pineapple samples was also investigated and a mathematical model based on the Zwietering modified Gompertz equation was used to obtain growth parameters of mesophilic bacteria, yeasts and moulds.The results showed that 1-MCP treatment and MAP in a N2O enriched atmosphere had a positive combined effect on the inhibition of respiration and ethylene production of fresh-cut pineapple and on its softening delay, confirming previous findings about 1-MCP and N2O preservative effects on fresh-cut fruit quality. This combined effect was not extended to the ripening index and colour maintenance, as MAP at 86.13 kPa of N2O did not add any benefit to that of the 1-MCP treatment. From a microbiological point of view, N2O MAP extended the shelf-life of the products of 3–4 d by increasing the lag phase of microbial growth. 相似文献
39.
A rapid peroxidase assay is proposed, using 3-mm diameter leaf discs, and based on the chronometric measurement of the oxidation of ascorbic acid, which is detected by means of the appearance of the blue colour of the benzidine-coupled reaction.The proposed method is adequately reproducible and sensitive for the diagnosis of iron deficiency in citrus. 相似文献
40.